Polymerase Chain Reaction: An Innovative Tool in Periodontal Diagnosis

Abstract

Bacterial species colonizing the surfaces of the human oral cavity play an important role in oral health and disease and thus an accurate means of identification is crucial. Traditionally, identification has been based on microscopy, biochemical tests, immunofluorescence staining and antibiotic sensitivity. However, these tests are labor-intensive and costly, providing sometimes inconsistent results that make identification rather tentative. Recently, molecular DNA-based techniques have been used to identify bacteria directly from clinical samples. Development of a microbiological diagnostic kit using this technology therefore requires the ability to extract the bacterial DNA from the plaque sample and amplify the specific DNA sequence of the target periodontal pathogen. Polymerase chain reaction has emerged as the most powerful tool for the amplification of the genes and their RNA transcripts. The focus of this review is to describe the current status of the DNA-based method PCR which has become a standard diagnostic and research tool in dentistry.